SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b970fed1af4e1e2fbf4c607a4fcb9907fe534e52e8e0a3e1e73f13664491512' 
  AND token = '09p23LlmOb2oqQvU8T9s04Qks4Jb0vXuJS5ClI1KTsw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}